fix(deps): update dependency source-map-loader to v4

package.json

@@ -64,7 +64,7 @@
     "postcss-reporter": "7.0.5",
     "promise-retry": "2.0.1",
     "react-svg-loader": "3.0.3",
-    "source-map-loader": "1.1.3",
+    "source-map-loader": "4.0.2",
     "stats-webpack-plugin": "0.7.0",
     "style-loader": "2.0.0",
     "stylelint": "16.1.0",

yarn.lock

@@ -7008,7 +7008,7 @@ [email protected], iconv-lite@^0.4.24:
   dependencies:
     safer-buffer ">= 2.1.2 < 3"
 
-iconv-lite@^0.6.2, iconv-lite@^0.6.3:
+iconv-lite@^0.6.3:
   version "0.6.3"
   resolved "https://registry.yarnpkg.com/iconv-lite/-/iconv-lite-0.6.3.tgz#a52f80bf38da1952eb5c681790719871a1a72501"
   integrity sha512-4fCk79wshMdzMp2rH06qWrJE4iolqLhCUH+OiuIgU++RB0+94NlDL81atO7GX55uUKueo0txHNtvEyI6D7WdMw==
@@ -11509,17 +11509,13 @@ source-list-map@^2.0.0:
   resolved "https://registry.yarnpkg.com/source-map-js/-/source-map-js-1.0.2.tgz#adbc361d9c62df380125e7f161f71c826f1e490c"
   integrity sha512-R0XvVJ9WusLiqTCEiGCmICCMplcCkIwwR11mOSD9CR5u+IXYdiseeEuXCVAjS54zqwkLcPNnmU4OeJ6tUrWhDw==
 
-source-map-loader@1.1.3:
-  version "1.1.3"
-  resolved "https://registry.yarnpkg.com/source-map-loader/-/source-map-loader-1.1.3.tgz#7dbc2fe7ea09d3e43c51fd9fc478b7f016c1f820"
-  integrity sha512-6YHeF+XzDOrT/ycFJNI53cgEsp/tHTMl37hi7uVyqFAlTXW109JazaQCkbc+jjoL2637qkH1amLi+JzrIpt5lA==
+source-map-loader@4.0.2:
+  version "4.0.2"
+  resolved "https://registry.yarnpkg.com/source-map-loader/-/source-map-loader-4.0.2.tgz#1b378721b65adb21e874928a9fb22e8a340d06a5"
+  integrity sha512-oYwAqCuL0OZhBoSgmdrLa7mv9MjommVMiQIWgcztf+eS4+8BfcUee6nenFnDhKOhzAVnk5gpZdfnz1iiBv+5sg==
   dependencies:
-    abab "^2.0.5"
-    iconv-lite "^0.6.2"
-    loader-utils "^2.0.0"
-    schema-utils "^3.0.0"
-    source-map "^0.6.1"
-    whatwg-mimetype "^2.3.0"
+    iconv-lite "^0.6.3"
+    source-map-js "^1.0.2"
 
 source-map-resolve@^0.5.0:
   version "0.5.3"